Zehang Zhuang

Decreased miR-320a promotes invasion and metastasis of tumor budding cells in tongue squamous cell carcinoma

We aimed to determine the specific miRNA profile of tumor budding cells and investigate the potential role of miR-320a in invasion and metastasis of tongue squamous cell carcinoma (TSCC). We collected tumor budding cells and paired central tumor samples from five TSCC specimens with laser capture microdissection and examined the specimens using a miRNA microarray. The specific miRNA signature of tumor budding cells was identified. We found that miR-320a was dramatically decreased in tumor budding cells. Knockdown of miR-320a significantly enhanced migration and invasion of TSCC cell lines. Suz12 was shown to be a direct target of miR-320a. Similar results were also observed in nude mouse models. Multivariate analysis indicated that miR-320a was an independent prognostic factor. Kaplan–Meier analysis demonstrated that decreased miR-320a and high intensity of tumor budding were correlated with poor survival rate, especially in the subgroup with high-intensity tumor budding and low expression of miR-320a. We concluded that decreased expression of miR-320a could promote invasion and metastasis of tumor budding cells by targeting Suz12 in TSCC. A combination of tumor budding and miR-320a may serve as an index to identify an aggressive sub-population of TSCC cells with high metastatic potential.

MicroRNA-218 promotes cisplatin resistance in oral cancer via the PPP2R5A/Wnt signaling pathway

Accumulating data suggest that microRNAs (miRNAs) play a pivotal role in the regulation of tumor cell sensitivity to chemotherapeutic agents. Although the roles of a few miRNAs have been identified in cisplatin resistance, little is known in regards to the concerted contribution of miRNA-mediated biological networks. In the present study, we demonstrated that microRNA-218 (miR-218) was significantly upregulated in cisplatin-resistant oral cancer cells. The results of cell viability and apoptosis assay showed that ectopic expression of miR-218 induced cell survival and resistance to cisplatin, whereas suppression of miR-218 caused apoptosis and enhanced sensitivity to cisplatin. Moreover, we identified PPP2R5A as a new direct target of miR-218 by using the dual luciferase reporter assay. Overexpression of miR-218 led to inhibition of PPP2R5A expression, whereas knockdown of miR-218 increased PPP2R5A levels. Introduction of PPP2R5A abrogated miR-218-mediated cell survival and drug resistance. Furthermore, suppression of miR-218 or PPP2R5A significantly promoted or reduced cisplatin-induced apoptosis, respectively. Finally, PPP2R5A overexpression or β-catenin knockdown inhibited miR-218-mediated Wnt activation and partially restored cell sensitivity. Our data revealed a molecular link between miR-218 and PPP2R5A/Wnt signaling and implicates miR-218 as a potential target for oral cancer therapy.

Interplay between ΔNp63 and miR-138-5p regulates growth, metastasis and stemness of oral squamous cell carcinoma

TP63 acts as a master regulator in epithelia development and in the progression of various cancers, but its role in oral cancer pathogenesis remains unknown. This study aimed to explore the role of TP63 in the progression of oral squamous cell carcinoma (OSCC). This study shows that ΔNp63, the predominant isoform of TP63, is significantly upregulated in OSCC tissues and cell lines compared with their normal counterparts, and its expression is closely correlated with pathological differentiation, lymph node metastasis and clinical stage in patients with OSCC. The overexpression of ΔNp63 promotes growth, metastasis and stem-like properties in OSCC cells, and ΔNp63 depletion significantly represses OSCC cellular phenotypes in vitro and in vivo. The ΔNp63 isoform transcriptionally suppresses miR-138-5p expression; restoration of miR-138-5p expression partially abolishes the effect of upregulating ΔNp63. This study also demonstrates that miR-138-5p directly targets ΔNp63, resulting in crosstalk with ΔNp63. The correlation between ΔNp63 and miR-138-5p was further validated in OSCC tissues and was found to be significantly associated with the prognosis of patients with OSCC. Therefore, our data reveal that the interplay between ΔNp63 and miR-138-5p promotes OSCC progression by regulating cell growth, metastasis and stemness.

Activation of adrenergic receptor β2 promotes tumor progression and epithelial mesenchymal transition in tongue squamous cell carcinoma

Tongue squamous cell carcinoma (TSCC) is more aggressive than other cancers in the head and neck region because of its potential for metastasis. Recently, β2-adrenergic receptor (β2-AR) has been reported to be a potential promoter in various types of solid cancer. However, the role of β2-AR and its effect on TSCC is not well documented. Histological staining, western blot analysis, migration and invasion assay were used. In this study, the expression of β2-AR was increased in TSCC tissue compared with adjacent non-cancerous epithelium. Further analysis demonstrated that increased expression of β2-AR was correlated with differentiation, lymph node metastasis and reduced overall survival rate in patients with TSCC. In vitro studies confirmed that activation of β2-AR can promote epithelial mesenchymal transition in TSCC by initiating an interleukin-6/Stat3/Snail1 pathway. These results suggest that β2-AR has an oncogenic role in TSCC and may be a potential therapeutic target in TSCC.

Abstract 2190: Theranostical nanoscale metal-organic frameworks-mediated rapid multiplexed microRNA detection and highly therapeutic efficacy in living oral cancer cells

Oral cancer represents the sixth most frequent cancer in the world, characterized by high poor prognosis and low survival rate due to local relapse and metastasis. MicroRNAs (miRNAs) have been discovered as diagnostic biomarkers and therapeutic targets for oral cancer. However, one of the major challenges of miRNAs-based theranostical approach is to achieve efficient and safe delivery. Thus, a reliable sensing strategy that can detect miRNAs expression levels in living cancer cells is urgently needed. Herein, a novel sensing platform based on nanoscale metal-organic framework (NMOF) conjugated with the fluorophores-labeled single-stranded DNA probe (p-DNA) was fabricated to monitor and inhibit multiplexed miRNAs expression in living oral cancer cells. The flow cytometry and confocal laser scanning microscopy (CLSM) were carried out to evaluate the expression levels of miRNAs in oral cancer cells. The miRNA inhibition efficiency was examined by RT-PCR. The effects of the complexes on tumor cell invasion and migration were assessed by transwell assay and wound healing. The flow cytometry, colony formation assay and CCK8 were used to assess cell apoptosis and proliferation. The results showed that NMOF works as fluorescence quencher of the labeled p-DNA. In presence of the target miRNA (including miR-7, miR-21, and miR-155), p-DNA was able to rapidly hybridize and release from the NMOF leading to the recovery of fluorescence in living cells, which can be detected in real-time. Moreover, RT-PCR results demonstrated that the multiplexed miRNAs could be effectively downregulated after treatment of p-DNA@NMOF, resulting in the simultaneous suppression of oral cancer cell proliferation, anti-apoptosis, migration and invasion in vitro. In summary, our study suggests that p-DNA@NMOF possess great potential for combining early diagnosis and gene therapy of oral cancer. Note: This abstract was not presented at the meeting. Citation Format: Pei Yu, Zehang Zhuang, Guihua Qiu, Haolin Chen, Yuying Zhao, Jinxiang Chen, Xiqiang Liu. Theranostical nanoscale metal-organic frameworks-mediated rapid multiplexed microRNA detection and highly therapeutic efficacy in living oral cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2190. doi:10.1158/1538-7445.AM2017-2190

Abstract 985: Downregulation of long noncoding RNA TINCR promotes invasion and metastasis and predicts poor prognosis in tongue squamous cell carcinoma

Background and aim: Recently long non-coding RNAs (lncRNAs) have emerged as new gene regulators involving in a number of developmental and tumorigenic processes. However, few lncRNAs have been well characterized in tongue squamous cell carcinoma (TSCC). The aim of this study is to determine whether lncRNAs play a role in TSCC progression. Methods: The expression profiles of lncRNAs and protein-coding genes in TSCC tissues and paired adjacent non-tumor tissues from 10 patients were compared by using lncRNA microarrays. TSCC-specific gene co-expression networks were constructed by differential expression analysis and weighted gene co-expression network analysis (WGCNA). Levels of these differentially expressed lncRNAs were verified in TSCC tissues (n = 45) using Quantitative real-time PCR (qRT-PCR) and further confirmed in another patient cohort (n = 103) by in situ hybridization (ISH). The effects of lncRNA on tumor cell invasion and migration were assessed by silencing or overexpressing the lncRNA in vitro. Results: A total of 815 lncRNAs and 1783 protein-coding genes were differentially expressed between TSCC tissues and paired adjacent non-tumor tissues. WGCNA showed that one of the co-expression networks was significantly enriched for biological process that was relevant to epithelial cell differentiation, among which, TINCR was significantly down-regulated. Both PCR and ISH analyses validated that the down-regulation of TINCR in tumor tissues compared with controls. The expression level of TINCR was associated with tumor size, differentiation, cervical lymph node metastasis status, clinical stage and outcomes in patients with TSCC.Patients with TINCR low expression had a reduced overall survival. COX regression analysis showed that TINCR can be served as an independent prognostic factor for patients with TSCC. More, ectopic transfection of TINCR dramatically suppressed cell invasion and migration in vitro. On the contrary, knockdown of TINCR led to p63 upregulation, and enhanced cell invasion and migration. Conclusion: Our study suggests that downregulation of TINCR plays a role in TSCC progression, at least partially, by regulating epithelial differentiation-associated genes. Citation Format: Zehang Zhuang, Cheng Wang, Nan Xie, Yue Wu, Jinsong Hou, Xiqiang Liu, Hongzhang Huang. Downregulation of long noncoding RNA TINCR promotes invasion and metastasis and predicts poor prognosis in tongue squamous cell carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 985.

Abstract 1084: Clinical significance of p63/miR-138 deregulation in tongue squamous cell carcinoma

BACKGROUND and AIMS: p63 is critical for the development and maintenance of stratified epithelial tissues. The role of p63 in tumorigenesis remains poorly defined. This study aims to determine the levels of p63 and miR-138 expression both in vitro and in vivo, and further to analyze their correlation with the clinicopathological parameters and prognosis in patients with tongue squamous cell carcinoma (TSCC). METHODS: Levels of p63 and miR-138 in TSCC and paired para-cancerous tissues were investigated by immunohistochemistry (IHC) and in situ hybridization (ISH), respectively. The correlations of p63 and miR-138 expression with the clinico- pathological parameters and prognosis of patients with TSCC were analyzed using SPSS 13.0 software package. Expression of p63 and miR-138 in TSCC cell lines (n = 5) was measured using immunoblot analysis and qRT-PCR, respectively. p63 was expressed transgenically, or knocked down with shRNAs in SCC9, SCC25, SCC15 and UM1 cell lines, and effects on cell invasion and migration were evaluated. RESULTS: Elevated level of p63 and reduced level of miR-138 was observed in TSCC tissues in comparison with paired para-cancerous tissues (p CONCLUSION: The dysregulation of p63 and miR-138 are common molecular events in TSCC progression. These findings suggest that p63 and miR-138 may collaboratively play a role in tongue carcinogenesis. Citation Format: Zehang Zhuang, Yun Wang, Cheng Wang, Nan Xie, Yue Wu, Jinsong Hou, Xiqiang Liu, Hongzhang Huang. Clinical significance of p63/miR-138 deregulation in tongue squamous cell carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1084.